Genetic characterization of the mite Varroa destructor (Acari: Varroidae) collected from honey bees Apis mellifera (Hymenoptera, Apidae) in the State of Santa Catarina, Brazil

Abstract

ABSTRACT. The mite Varroa destructor is an ectoparasite that is considered a major pest for beekeeping with European honey bees. However, Africanized bee colonies are less threatened by this ectoparasite, because infestation levels remain low in these bees. The low reproductive ability of female mites of the Japanese biotype (J), introduced to Brazil early in the 1970s was initially considered the main factor for the lack of virulence of this parasite on Africanized bees. In other regions of the world where the Korean (K) biotype of this mite was introduced, there have been serious problems with Varroa due to the high reproductive potential of the mite. However, a significant increase in the reproductive rate of females of Varroa in Brazil has been recently demonstrated; the cause could be a change in the type of Varroa in the bee colonies. We evaluated the prevalence of haplotypes J and K in mite samples collected from the State of Santa Catarina and from the island of Fernando de Noronha in the State of Pernambuco. The analysis of the mitochondrial genome (PCR + RFLP) revealed haplotype K in all samples from Santa Catarina and haplotype J in all samples from Fernando de Noronha. The analysis of microsatellites (nuclear genome) in bees from Fernando de Noronha Varroa destrutor haplotypesshowed only the specific alleles of haplotype J, while in bees from Santa Catarina, these alleles were found in only 2.8% of the samples. The high frequency of individuals with Korean genetic material is probably to the reason for the current high reproductive capacity of the mite V. destructor recorded in Santa Catarina.

Honeybee health in South America

“…The presence of Varroa mites in Venezuela and Chile is recent: it was detected in Venezuela in 1991 (Principal et al 1991) and in Chile in 1992 (Casanova and Perruolo 1992). Current studies have demonstrated that the Korean haplotype is cosmopolite in SA (Strapazzon et al 2009;Maggi et al 2012), to the point that the Japanese haplotype is nearly absent in SA countries. The island of Fernando de Noronha (Brazil) is the exception, where Italian bees were introduced into colonies that had been transported from mainland Brazil in 1984 (De Jong andSoares 1997).…”

Natural Varroa mite-surviving Apis mellifera honeybee populations

“…Importantly, the Island of Fernando de Noronha is still parasitized by the original Japanese mite haplotype that was introduced from mainland Brazil when the island's honeybee population was first established (Strapazzon et al 2009). The presence of the less virulent Japanese mite haplotype on the island could explain how this honeybee population manages to survive with uncontrolled Varroa mite infestation.…”

Enfraquecimento e perda de colônias de abelhas no Brasil: há casos de CCD?

“…No Brasil, as abelhas africanizadas apresentam algumas características que favorecem a resistência ao ácaro, inclusive elevada infertilidade do parasita nesse biótipo (Rosenkranz, 1999), o que pode explicar os baixos níveis de infestação observados no país (Strapazzon et al, 2009;.…”